It's Josh's birthday, so Kate and Owen decide to organise him a fancy dress party. Josh is not keen, but relents in the hope that it might give him a chance with Lucy who lives upstairs. Meanwhile, Kate meets her ex-boyfriend's new girlfriend Cath who is obsessed with youtube videos and will not be deterred by either lack of interest or buffering. And, inevitably, Geoff pops by the party wearing a suitably impractical costume.